Induction of Arabidopsis gdh2 gene expression during changes in redox state of the mitochondrial respiratory chain

Abstract

Expression of the gdh2 gene encoding the alpha-subunit of mitochondrial glutamate dehydrogenase depends on redox state of the mitochondrial electron transport chain. Treatment of Arabidopsis thaliana cell suspension with antimycin A, a respiratory chain complex III inhibitor, resulted in an increase in gdh2 transcripts within 2 h. Inhibition of complex I by rotenone did not influence the transcript level, but treatment with potassium cyanide, a complex IV inhibitor, also increased the transcript content. Thus, gdh2 gene expression obviously responds to changes in the respiratory chain segment localized between complexes I and III. Lack of activation of gene expression after treatment of a cell suspension with hydrogen peroxide and the prooxidant paraquat and results of experiments with antioxidants suggest that gdh2 gene expression is not associated with increased content of reactive oxygen species generated during inhibition of the electron transport chain. Protein phosphorylation by serine/threonine protein kinases is the essential step required for signal transduction into nucleus resulting in the induction of gdh2 expression.

Molecular Signatures in Arabidopsis thaliana in Response to Insect Attack and Bacterial Infection

“…The MAP-kinase gene MPK1 participates in pathogen signalling, and its kinase activity increases in response to mechanical injury [59]. Glutamate dehydrogenase 2 ( GDH2 ), the alpha-subunit of glutamate dehydrogenase, is a mitochondrial protein that has been reported to be responsive to diverse environmental stresses [60]. Arabidopsis heat shock factor ( HSF4 ) regulates the expression of heat shock proteins [61].…”

Deamination role of inducible glutamate dehydrogenase isoenzyme 7 in Brassica napus leaf protoplasts

“…1), are also known to produce ROS during the preparation procedure , thus reinforcing the proposed link between ROS production and the GDH isoenzyme pattern. In contrast, recent results from an Arabidopis thaliana cell suspension suggest that it is the redox state of the mitochondrial electron transport chain itself, rather than ROS production, that regulates the expression of GDH2 and hence GDH isoenzyme composition (Tarasenko et al, 2009).…”

Expression of genes encoding subunits of respiratory complexes in Arabidopsis leaves depends on light

“…Arabidopsis cDNA obtained as described in [8] was used as a template for amplifica tion. DNA fragments were labeled using PCR in the presence of [α 32 P]dATP (IRM, Russia) in a quantity of 100 μCi per sample as described previously [9].…”

“…Hybridization was performed at 42°C in the same buffer containing a radiolabeled DNA probe that was preliminarily denatured by incubation at 95°C for 5 min. Hybridization was performed for 18 h. The membrane was washed as described in [9]. Before repeated hybridization, the membrane was washed from the unbound probe by incubation in 0.5% SDS at 95°C for 40 min.…”